staging: comedi: check comedi_auto_config() params

Do some minimal error checking of the parameters of
`comedi_auto_config()`.  Just make sure the `hardware_device` and
`driver` parameters are non-NULL.

Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Reviewed-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/staging/comedi/drivers.c b/drivers/staging/comedi/drivers.c
index 4724f275830cfe216a0dbde50d91bf60a6758ced..4460814d5344c4e0289bd7d13495ecccd8b29ad4 100644 (file)
--- a/drivers/staging/comedi/drivers.c
+++ b/drivers/staging/comedi/drivers.c
@@ -410,6 +410,16 @@ int comedi_auto_config(struct device *hardware_device,
        struct comedi_device *comedi_dev;
        int ret;
 
+       if (!hardware_device) {
+               pr_warn("BUG! comedi_auto_config called with NULL hardware_device\n");
+               return -EINVAL;
+       }
+       if (!driver) {
+               dev_warn(hardware_device,
+                        "BUG! comedi_auto_config called with NULL comedi driver\n");
+               return -EINVAL;
+       }
+
        if (!driver->auto_attach) {
                dev_warn(hardware_device,
                         "BUG! comedi driver '%s' has no auto_attach handler\n",